Safety door of the biparting type



'Nov. 15, 1949 G. ANDERSON 2,488,257

SAFETY DOOR OF THE BI-PARTING TYPE Filed April 21, 1945 Patented Nov. 15, 1949 SAFETY-'DOOR'OF THE BIPARTIN G TYPE -.Ge0rge Andersomsummitrhl. Jusassignor to Ciba Pharmaceutical Products, Incorporated, :Sum-

mit, N. J.,..a corporationof New .Jersey Application April 21, 1945,Serial N0.'-'589;591

-8 Claims.

Thestpresent invention relates to doors, particu- .larly those-ofthe vertical vbi-parting type, and to a safety device therefor.

Industrial type elevator :installatiens-freight elevators vand-theilike -are generally provided withzvertically movable bi-parting doors. The door-sections :are generally guided ;on vertical guides and are interconnected in mutually counterbalancingrelationship. One of the door sections,; generally .the upper one, is provided with a handle or strap whereby it may be pulled in .one or the other direction to open or closethe door, the other section being simultaneously actuated due to-the aforesaid interconnection.

The closing'operation is realized in a single bar, depending. fromsaid uppersection into overlappingrelation with the seam between the two sections when the .dooris closed. This sea-ling member, usually required by the insurance companiesprimarily to prevent fire from spreading from one side of the door to the other, .has however proven to be a very great accident hazard since it operates as a cutting knife blade, if ever the operator should be inattentive or negligent and'inadvertently'insert his hand between the two closing edges of the door.

A primary object of the invention is the embodiment of a door, more particularlyof the vertical bi-parting type, wherein the aforesaid hazard is eliminated and wherein incidentally the hard shocks and consequent undue wear "caused a.

by slamming the' door sections together are also eliminated.

Briefly stated, the invention is based upon'the principle of enforcing 1 a two-stage movement, in-

stead of the hitherto conventional single movement, when closing-the door, and also for'cingthe operator to use both hands'ior the second-stage of the two-stage movement, thus preventing him from having a freehand which hecould accidentally insert between the closing door sections.

Realization of the object of the invention is achieved, according to the latter, by installing a brake piston arrangementwhich determines and defines the extent: of the-first stage of the aforesaid tWo-stage movement and terminates this stage-:inca :smoothmanner freefrom shocka'or slamming. The second stage of themiovement entails the pushingrof a release rbuttonbyttthe operatorwithaone hand,;thereby .short circuiting the brake andmakingittpossible"to bring :the door :sections to" final :closing position "with the othervhand.

The foregoing sets iforth generally the "purpose of the invention, a presently-preterred method of reducing the invention to; practice-and its various broad features andadvantages. Other features and advantages of the invention. will be apparent from the following detailed description thereof with :reference to the -accompanying sheet of drawing.

-Onrthe saidsheet,

..Fig.;1 is a schematic representation in elevation of a relationship of; parts-according to the present invention,-andillustrating more particularlythe condition whichprevails attheend of th first stageof -.the doorecl-os'mg. movement;

Fig. 2 is a sectional view taken alongh'ne-Z-J of .Eig.;l;

v.Fig. 3-.is,-a-sectional view-illustrating a second embodimentwofthe invention, with the .partsi-n their :respective positions as the door is being opened;

.Fig. 4 is a sectional view corresponding; to that of Fig. 3,- .butshowingthe-parts in their respectivepositions at :the end of the first stage of the twoestage door-closing movement; and

.Fig.., 5 .is a sectional view showing the parts of Figs. 3 and :4..at.the;end of the second or final stage of the closingimovement.

.Referring first. to the embodiment according to Eigs. .1 and. 2,. the .door is diagrammatically illustrated. as avertical.bi-partingdoor, such .as may be employed for ..closing anelevatorhatchway opening. The .door comprises ,an upper. section [0 and. a lowersectionl linterconnectedin counterbalancing relationship .in any suitable and desirable conventional manner, was for example through the, medium of ,a .ehain and; pulley .arrangement 12. One end ofthechain mayheattached to brackets ltprovided .on the ends-of door section it), while the,othe1' ,end ,of the .chain may conveniently be secured to the. respective lateralextensionsof the metallic sill M which is mounted at the upper edge of door section II as shown. The pulling force-necessary to raise or lower the upper section H! may be appliedtheretothr-ough'the hand-leis or with aidof a-similar device such' as' a strap or the like attached to the door. As the-upper section is raised, the lower section I l f is sinn1ltaneously lowered, and vice- .versa. Conventional door guides, supports, etc.

of any object between'the abutting edges of the door.

In accordance with the embodiment being described, a plurality of brake devices may be mounted preferably on the inside of the door.

These brake devices are so contrived that, when the upper door section is pulled down to close the door, positive stopping in smooth and silent manner of the respective door sections at a predetermined distance apart from each other is assured. Thus, it is impossible for the operators hand-to be caught in between the closing door sections. In order to bring the latter into wholly closed or abutting relationship, the operator has to use one hand to actuate a release device and the other hand to effect the final closing movement. Both hands of the operator are thus necessarily positioned elsewhere than between the closing door sections.

Each brake device may conveniently comprise a cylinder [1 secured in place by means of straps or the like asshown. Each cylinder is provided with a reciprocatory piston Ha, the piston rod of which extends. through the lower end of the cylinder and terminates in a weighted bumper head I 8 of any suitable configuration with the terminal portion l9 thereof preferably constituted of felt, rubber or other resilient and noise-absorbing material. The upper end of each cylinder I1 is connected by means of a conduit 19 or the like, to a normally closed bleeder valve release mechanism 20. r r

This release mechanism may conveniently comprise a valve casing 2! provided with a valve seat which is normally closed by a valve member 22 under the influence of spring 23. Connected with casing 2! as shown is a casing 24 for a flap valve or the like 24a. The upper end of the stem of valve member 22 preferably terminates in a press button 25. In order that button 25 may be depressed from either side of the door section II), a handle rod 26 may be provided which extends through an opening in the said section in which it is centrally pivoted.

1 Operation of the device is essentially as follows: When the door is opened, i. e. section It] is raised, each piston Ha descends in its cylinder I6 by the action of gravity so that when the hatchway is open, the piston rod and bumper head l8 depend to a slight extent below the lower edge of section I0. During the downward movement of piston, flap valve 24a opens to allow air to flow into the cylinder 16;,The' general relationship of parts at this time is shown in Fig. 3.

Closing of the door takes place, as aforesaid, in two stages of movement. The first stage takes place in the usual way when the upper section III is pulled down by handle I5. As the upper section approaches the lower section I I, each head l8 engages sill M which is in alinement therewith (see Fig. 4) and each piston He is moved upwardly in its cylinder. This causes closing of valves 24a and, valves 22 being spring-closed, the air trapped in the cylinders I6 is compressed 4 until further downward movement of the section i0 is prevented. At this stage, generally exemplified in Fig. 4, there is a safety distance 26 between sections ill and II. The dimensions of the parts may preferably be correlated so that a safety distance 26 of about 2 inches is provided at the end of the first stage of the closing movement.

To start the second part of the closing movement and thereby bring the doors to a full close,

the operator has to depress push button 25 whereby the accumulated air pressure-in the cylinders ll is relieved and, consequently, the brake short circuited. As one hand of the operator then pulls on the handle or strap I5 to close the door, the other hand is forced to keep the release button 25 pushed open and this serves as a check against accidentally placing a hand or fingers between the door edges, regardless of whether the door is closed from the elevator cabin (inside) or corridor side (outside). A handle or strap I5 is, of course, also provided on the outside of the door section Ill.

While the embodiment of Figs. 1 and 2 involves two brake devices and a single common release mechanism, use may also be made of but a single brake device located at any suitable point on the upper door section. When but a single brake device is used, the release mechanism is situated directly above the cylinder l6 as shown in Figs. 3, 4 and 5.

' It will be understood of course that the foregoing detailed description of presently-preferred embodiments of the invention is essentially intended to be illustrative and not limitative in character. Thus, various minor changes within the spirit and scope of the invention as recited in the appended claims will occur to the expert in the 'art. For example, alternative means may be provided for efiecting depression of button 25 from the outside of the door; the flap valve 24:; may be of the ball type; button 25' and flap valve 24 may be combined in one unit; the two cylinders l'l may be combined in one unit; or the whole mechanism comprising cylinder I! flap valve 24 and buttons 25 may be combined in one preassembled unit to fit in a reset of the door, etc. The invention is manifestly applicable to doors used for closing other openings than elevator hatchway openings and may, for instance, be used for warehouse door openings. It may also be applied to single section doors, such as those commonly used on dumbwaiters and the like.

Having thus disclosed the invention, what is claimed is: V r

1. A safety door of the bi-parting type and comprising upper and lower door sections which are connected together in counterbalanced relationship and which are vertically movable toward each other for closing the door and away from each other for opening the door, and means mounted on and movable with said upper section and engageable by said lower door section at a point during closing movement of said sections whereby the latter may, in the first instance, be positively maintained spaced apart from each other short of complete closure, and means for releasing said first-named means whereby com-' plete closure may be realized.

2. Brake means for a safety door of vertical bi-parting type, comprising a brake cylinder. mounted on the upper section of said door, a piston reciprocable in said cylinder and depending therefrom, a normally closed valve in said cylinder above said piston, said piston being engageable by the lower section of said door during closing movement thereof, whereby air contained in said cylinder is compressed and said sections are stopped short of complete closure, and means for opening said valve to relieve the resultant compression in said cylinder whereupon complete closure of said door may be realized.

3. Brake means for a safety door of the vertical bi-parting type, comprising a brake cylinder mounted on the upper section of said door, a piston reoiprocable in said cylinder and depending therefrom, a normally closed valve in said cylinder above said piston, said piston being engageable by the lower section of said door during closing movement thereof, whereby air contained in said cylinder is compressed and said sections are stopped short of complete closure, means for opening said valve to relieve the resultant com pression in said cylinder whereupon complete closure of said door may be realized, and means for actuating said vaive opening means from both sides of said door.

4. In a vertical bi-parting door installation in which the door sections are connected together in counterbalanced relationship, means depending from the upper door section and engageable by the lower door section to positively stop said sections short of complete closing engagement, said depending means being releasable for vertical displacement to permit complete ciosing engagement of said sections, and means for releasing said depending means.

5. In a vertical bi-parting door in which the door sections are connected together in counterbalanced relationship, a plurality of brake cylinders mounted on the upper door section, a piston depending from each cylinder and engageable and movable by the lower door section during closing movement of said door sections, means for holding said pistons against displacement by said lower door section at a point short of complete closure of said door, and means for simultaneously releasing said pistons whereby complete closure may be realized.

6. Brake means for a safety door of the biparting type, comprising a brake cylinder mounted on one section of said door, a piston reciprocable in said cylinder and projecting from one end thereof, said piston being engageable by the other section of said door during closing movement thereof, whereby air contained in said cylinder is compressed and said sections are brought to a full stop short of complete closure, a one-Way inlet Valve for air into said cylinder, said valve being positively closed by pressure exerted thereon from said piston during said closing movement of the door, a normally closed relief valve mounted on said cylinder at the other end thereof, and means for opening said relief valve to relieve the compression established in said cylinder during said closing movement, whereupon complete closure of said door may be realized.

7. Brake means for a safety door of the biparting type, comprising a brake cylinder mounted on the upper section of said door, a piston reciprocable in said cylinder and depending therefrom, said piston being engageable by the lower section of said door during closing movement thereof, whereby air contained in said cylinder is compressed and said sections are brought to a full stop short of complete closure, a one-way inlet valve for air into said cylinder, said valve being positively closed by pressure eX- erted thereon from said piston during said closing movement of the door, a normally closed relief valve mounted on said cylinder at the top thereof, and means for opening said relief valve to relieve the compression established in said cylinder during said closing movement, Whereupon complete closure of said door may be realized.

8. Brake means for a safety door of the biparting type, comprising a brake cylinder mounted on one section of said door, a piston reciprocable in said cylinder and projecting from one end thereof, said piston being engageable by the other section of said door during closin movement thereof, whereby air contained in said cylinder is compressed and said sections are brought to a full stop short of complete closure, a one-way inlet valve for air into said cylinder, said valve being positively closed by pressure exerted thereon from said piston during said closing movement of the door, a normally closed relief valve mounted on said cylinder at the other end thereof, and means operable from either side of said door for opening said relief valve to relieve the compression established in said cylinder during said closing movement, whereupon complete closure of said door may be realized.

GEORGE ANDERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 910,654 Evans Jan. 26, 1909 1,095,370 Bardsley May 5, 1914 1,145,881 Doyle July 13, 1915 1,590,414 Bosserdet June 29, 1926 2,083,762 Waldman June 15, 1937 2,092,531 Dimick Sept. 7, 1937 

